Bituminous composition with improved &#39;walk-on-ability&#39; and its use in roofing applications

ABSTRACT

Disclosed is a bituminous composition that comprises a bituminous component (A), an elastomer component (B), preferably a block copolymer of a conjugated diene and a monovinylaromatic hydrocarbon, and an additive (C), wherein the additive is a compound of the general formula 
 
Ar—R—Ar  (I) 
wherein each “Ar” independently is a benzene ring or fused aromatic ring system of 6 to 20 carbon atoms, substituted by at least one hydroxyl group, and “R” is an optionally substituted divalent radical comprising 6 to 20 atoms in the backbone and at least one amide and/or ester group in the backbone. These compositions are disclosed to be particularly useful in the preparing and repair of roofing.

CROSS-REFERENCE TO RELATED APPLICATIONS

The present application is a continuation of copending, commonlyassigned U.S. patent application Ser. No. 10/655,668, having the sametitle and filed 5 Sep. 2003 (now U.S. Pat. No. ______), which is acontinuation in part of copending, commonly assigned U.S. patentapplication Ser. No. 10/381,607, having the same title and filed 26 Mar.2003; which Application claims priority from PCT Application NumberPCT/EP01/11305, filed 28 Sep. 2001; which Application claims priorityfrom European Patent Application Number EP 00308546.1 filed 28 Sep.2000.

BACKGROUND OF THE INVENTION

1. Field of the Invention

The present invention relates to bituminous compositions. The presentinvention particularly relates to bituminous compositions including anelastomer component.

2. Background of the Art

A major proportion of the roofing felts applied nowadays are made ofmodified bituminous compositions, e.g., bituminous compositionscomprising a bitumen component and an elastomer component, typically astyrenic block copolymer such as SBS(polystyrene-polybutadiene-polystyrene) SEBS(polystyrene-poly[ethylene-butylene]-polystyrene); SIS(polystyrene-polyisoprene-polystyrene) and SEPS(polystyrene-poly[ethylene-propylene]-polystyrene) and the like.Advantages of modified bituminous compositions over traditional systems(blown bitumen) include: improved fatigue resistance (the accommodationof repeated thermal movements of the roof); improved flexibility(especially at low temperature, enabling contractors to lay felt undercolder weather conditions than with conventional bitumen); improvedstrength (to allow a reduction in the number of plies of felt byreplacing in whole or part the traditional blown bitumen coated system);improved resistance to (permanent) deformation at short and longerloading times (so-called ‘walk-on-ability’); and improved elasticity,resulting in a greater capacity to bridge movement of crack and joints.

Although modified bituminous compositions satisfy all of the aboverequirements in as much as these materials having excellent high and lowtemperature properties (i.e. cold bending resistance at −30 to −25° C.and flow resistance at 80 to 100° C.), improvement is still desired.

A property of particular importance in roofing applications is thewalk-on-ability mentioned before. In case of inadequate walk-on-ability,torching, which is one of the most widely used application methods forbituminous roofing felts, could lead to undesired surface effects and/ordamage due to insufficient resistance to deformation. An assessment ofthe resistance of a composition to withstand such working traffic iscurrently ranked by the penetration value (ASTM D5-94) at 50° C. Areduction in PEN value, i.e. improving the resistance to deformation,whilst maintaining the performance properties and especially the lowtemperature properties would be highly desirous.

It has now been found that walk-on-ability of modified bituminouscompositions may be improved without (significant) effect on the otherperformance properties of the compositions. As a result, modifiedbituminous compositions with an improved balance of properties are nowavailable. Alternatively, modified bituminous compositions may now bemade of relatively soft bitumen, that would otherwise have insufficientwalk-on-ability (too high PEN value).

SUMMARY OF THE INVENTION

In one aspect, the present invention is a bituminous compositioncomprising a bituminous component (A), an elastomer component (B), andan additive (C), wherein the additive is a compound having the generalformula:Ar—R—Ar  (I)wherein each “Ar” independently is a benzene ring or fused aromatic ringsystem of 6 to 20 carbon atoms, substituted by at least one hydroxylgroup, and “R” is an optionally substituted divalent radical comprising6 to 20 atoms in the backbone and at least one amide and/or ester groupin the backbone.

In another aspect, the present invention is a composition useful forpreparing or repairing roofs comprising a bituminous component (A), anelastomer component (B), and an additive (C), wherein the additive is acompound having the general formula:Ar—R—Ar  (I)wherein each “Ar” independently is a benzene ring or fused aromatic ringsystem of 6 to 20 carbon atoms, substituted by at least one hydroxylgroup, and “R” is an optionally substituted divalent radical comprising6 to 20 atoms in the backbone and at least one amide and/or ester groupin the backbone.

In still another aspect, the present invention is a process forpreparing a bituminous composition comprising admixing a bituminouscomponent (A), an elastomer component (B), and an additive (C), whereinthe additive is a compound of the general formula:Ar—R—Ar  (I)wherein each “Ar” independently is a benzene ring or fused aromatic ringsystem of 6 to 20 carbon atoms, substituted by at least one hydroxylgroup, and “R” is an optionally substituted divalent radical comprising6 to 20 atoms in the backbone and at least one amide and/or ester groupin the backbone.

Another aspect of the present invention is a process for preparing orrepairing roofs comprising using a composition comprising a bituminouscomponent (A), an elastomer component (B), and an additive (C), whereinthe additive is a compound having the general formula:Ar—R—Ar  (I)wherein each “Ar” independently is a benzene ring or fused aromatic ringsystem of 6 to 20 carbon atoms, substituted by at least one hydroxylgroup, and “R” is an optionally substituted divalent radical comprising6 to 20 atoms in the backbone and at least one amide and/or ester groupin the backbone and the elastomer component and the additive are admixedwith each other prior to being admixed with the bituminous component forpreparing or repairing the roofs.

BRIEF DESCRIPTION OF THE FIGURES

For a detailed understanding and better appreciation of the presentinvention, reference should be made to the following detaileddescription of the invention and the preferred embodiments, taken inconjunction with the accompanying figures, wherein:

FIG. 1 is a graph showing the relationship between indention and theconcentration of MD 1024 additive in a bitumen composition.

FIG. 2 is graph showing the resistance to deformation of a referencesample and a bituminous composition of the present invention.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

The components of the bituminous composition will be describedhereafter.

Additive

The additive used in the present invention is a compound of the generalformula:Ar—R—Ar  (I)wherein each “Ar” independently is a benzene ring or fused aromatic ringsystem of 6 to 20 carbon atoms, substituted by at least one hydroxylgroup, and “R” is an optionally substituted divalent radical comprising6 to 20 atoms in the backbone and at least one amide and/or ester groupin the backbone.

Suitably, each “Ar” is a benzene ring or a fused aromatic ring system of6 to 10 carbon atoms, preferably a benzene ring. The benzene ring orfused aromatic ring system is substituted by at least one hydroxylgroup, although more hydroxyl groups may be present. Suitably, thehydroxyl group or one of the hydroxyl groups is substituted in the para,or 4-position. In addition, each “Ar” may independently carry one ormore substituents, preferably alkyl groups of 1 to 10 carbon atoms, mostpreferably at a position or positions adjacent to hydroxyl group(s).Most suitably, both “Ar” are 3,5-dialkyl-4-hydroxylphenyl groups,preferably 3,5-di-tert-butyl-4-hydroxylphenyl groups.

The divalent radical “R” may be represented by the general formula:˜˜˜[C(═O)X]n˜˜˜  (II)wherein “C(═O)X” represents an amide or ester group, “X” being an oxygenor nitrogen atom, preferably an amide group; and “n” the number of suchgroups. These groups, in case “n” equals 2 or more, may be adjacent toeach other but need not be. Suitably, “n” may vary from 1 to 4.Preferably “n” is 2 or 4, most preferably 2. Preferred examples ofradical “R” include:—R¹XC(═O)C(═O)XR¹—  (III)—R¹XC(═O)—R²—C(═O)XR¹—  (IV)—R¹C(═O)X—R²—XC(═O)R¹—  (V), and—R¹XC(═O)—R²—XC(═O)R¹—  (VI),wherein “R¹” is a C1-4 hydrocarbonylene group, preferably an ethylenegroup; “X” is as defined above; and “R²” is an organic bridging group of1 to 10 atoms in its backbone or a substituted organic bridging group of1 to 10 atoms in its backbone, such as a C1-10 hydrocarbonylene group,preferably a n-hexylene group, or a group of such length containing twoamide or ester groups, preferably amide groups in its bridge.

In case “R²” is substituted, then it may be substituted with one or moreof a variety of substituents, including alkaryl groups carrying an “Ar”group, and the like.

The preferred additive may hence be selected from, e.g., IRGANOX®MD-1024; IRGANOX 1098; IRGANOX 259 or NAUGARD® XL-1 and the like. Also acombination of such additives may be used. The most preferred additiveis bis(3,5-ditertbutyl-4-hydroxyphenylethylamino)dicarbonic acid amide,available as MD-1024 from Ciba-Geigy.

The additive may be added in any amount in the range of 0.01 to 5% wt,typically in an amount of 0.1 to 2% wt, based on total bituminouscomposition. The preferred amount depends on e.g. (I) the selectedadditive(s); (II) the ratio of elastomer component (B) versus bitumencomponent (A); (III) the nature of elastomer component (B) and ofbitumen component (A); and (IV) the presence of other components, suchas fillers. Nonetheless, little experimentation will be required to finda suitable amount of additive to improve the overall balance ofproperties of the bituminous composition.

Bitumen

The bituminous component present in the bituminous compositionsaccording to the present invention may be a naturally occurring bitumenor derived from a mineral oil. Also petroleum pitches obtained by acracking process and coal tar can be used as the bituminous component aswell as blends of various bituminous materials. Examples of suitablecomponents include distillation or “straight-run bitumens”,precipitation bitumens, e.g. propane bitumens, blown bitumens, e.g.catalytically blown bitumen or multigrade, and mixtures thereof. Othersuitable bituminous components include mixtures of one or more of thesebitumens with extenders (fluxes) such as petroleum extracts, e.g.aromatic extracts, distillates or residues, or with oils. Suitablebituminous components (either “straight-run bitumens” or “fluxedbitumens”) are those having a penetration of in the range of from 50 to250 dmm at 25° C. Generally a straight run or distilled bitumen having apenetration in the range of from 100 to 250 dmm will be the mostconvenient to use. Within the scope of the invention, bitumens ofdifferent level of compatibility may be used.

Elastomer

The bituminous composition according to the invention contains at leastone elastomer component (B). Elastomers are generally associated withpolymers of dienes, such as butadiene or isoprene, or with copolymers ofsuch dienes with a monovinylaromatic hydrocarbon, such as styrene. It isemphasized that the elastomer used in the composition of the inventionis not restricted to such polymers or copolymers. Suitable elastomersinclude polyesters, polyacrylates, polysulfides, polysilicones andpolyesteramides, provided they show an elastomer behaviour.

Preferably, at least one block copolymer comprising at least twoterminal blocks of a poly(monovinylaromatic hydrocarbon) and at leastone block of one or more conjugated dienes or a (partially) hydrogenatedversion thereof is used as elastomer component. Suitable conjugateddienes are those with from 4 to 8 carbon atoms per monomer, for examplebutadiene, 2-methyl-1,3-butadiene (isoprene),2,3-dimethyl-1,3-butadiene, 1,3-pentadiene and 1,2-hexadiene, inparticular butadiene and isoprene, and mixtures thereof. Suitablemonovinylaromatic hydrocarbons are o-methyl styrene, p-methyl styrene,p-tert-butylstyrene, 2,4-dimethylstyrene, a-methylstyrene, vinylnaphthalene, vinyl toluene, vinyl xylene, and the like or mixturesthereof, and in particular styrene.

These block copolymers may be linear or branched, and symmetric orasymmetric. A-preferred-example of a suitable block copolymer is thetriblock copolymer of the configuration A-B-A, in which “A” represents apolyvinylaromatic hydrocarbon block, and “B” represents a polydieneblock. These block copolymers may be further defined e.g. by the contentof monovinylaromatic hydrocarbons in the final block copolymer, theirmolecular weight and their microstructure, as discussed hereinafter.

The content of monovinylaromatic hydrocarbons of the final blockcopolymer suitably ranges from 10 to 70, more preferably from 20 to 50%wt (based on the total block copolymer).

The polymer blocks of monovinylaromatic hydrocarbons (“A”)advantageously have an apparent molecular weight in the range from 2,000to 100,000, in particular from 5,000 to 50,000. The polymer blocks ofconjugated dienes (“B”) preferably have an apparent molecular weight inthe range of from 25,000 to 1,000,000, particularly from 30,000 to150,000.

With the term “apparent molecular weight” as used throughout thespecification is meant the molecular weight of the polymer (block), asmeasured with gel chromatography (GPC) using polystyrene calibrationstandards (according to ASTM 3536).

Through modification of the polymerization, it is possible to direct theconjugated dienes to propagate in a manner wherein the carbon atoms of asingle unsaturated bond are incorporated in the backbone, or in a mannerwherein all carbon atoms of the unsaturated conjugated bonds areincorporated in the backbone. With respect to the former manner,poly(conjugated dienes) are defined by their vinyl content, referring tothe unsaturated bond that is now attached alongside the polymerbackbone.

Techniques to enhance the vinyl content of the conjugated diene portionare well known and may involve the use of polar compounds such asethers, amines and other Lewis bases and more in particular thoseselected from the group consisting of dialkylethers of glycols. Mostpreferred modifiers are selected from dialkyl ether of ethylene glycolcontaining the same or different terminal alkoxy groups and optionallybearing an alkyl substituent on the ethylene radical, such as monoglyme,diglyme, diethoxyethane, 1,2-diethoxypropane,1-ethoxy-2,2-tert-butoxyethane, of which 1,2-diethoxypropane is mostpreferred.

Suitably, the total vinyl content of the block copolymer is at least 6%wt (based on the blocks of poly(conjugated diene)), preferably in therange of from 8 to 80, more preferably in the range of from 25 to 55%wt.

The preparation of block copolymers is known in the art. In GB1538266 anumber of methods are described. For example, block copolymers may beprepared by coupling at least two diblock copolymer molecules together,using suitable coupling agents such as adipates (e.g., diethyl adipate)or silicon-compounds (e.g., silicon tetrachloride,dimethyldichlorosilane, methyldichlorosilane orgamma-glycidoxypropyl-trimethoxysilane) or a nucleus prepared byoligomerization of di- or tri-vinyl benzene. Other coupling agents canbe selected from polyepoxides, such as epoxidized linseed oil, orepoxidized bisphenols (e.g. the diglycidylether of bisphenol A),polyisocyanates (e.g., benzo-1,2,4-triisocyanate), polyketones (e.g.,hexane-1,3,6-trione), polyanhydrides or polyhalides (e.g.,dibromoethane) and the like.

Using coupling agents, a residue of uncoupled diblock copolymer mayremain in the final product, referred to as the “diblock content”. Wherethe block copolymer is prepared via a technique where no diblock isspecifically prepared or isolated, such as in full sequentialpreparation, it is known that the final amount of diblock can beadjusted e.g. by reinitiation. The diblock content may for instance bein the range of from 5 to 25% wt and more preferably from 10 to 25% wt,based on the elastomer component.

The hydrogenation of the block copolymer, if desired, may be carried outas described in the above British Patent Specification. Further examplesof suitable block copolymers, and their preparation, may be found forinstance in EP0006674; EP0238149; EP0667886; EP0317025; EP0506195;EP0756611; U.S. Pat. No. 5,189,083; U.S. Pat. No. 5,212,220; U.S. Pat.No. 5,141,986; U.S. Pat. No. 544,775; U.S. Pat. No. 5,451,619; U.S. Pat.No. 5,718,752; U.S. Pat. No. 5,854,335; U.S. Pat. No. 5,798,401; U.S.Pat. No. 3,231,635; U.S. Pat. No. 3,251,905; U.S. Pat. No. 3,390,207;U.S. Pat. No. 3,598,887; U.S. Pat. No. 4,219,627; EP0413294; EP0387671;EP0636654; and WO0422931, all included herein by reference.

Elastomer component (B) is suitably present in the bituminouscomposition in an amount in the range of from 2 to 20, more preferablyfrom 10 to 15% wt (based on the total bituminous composition).

Additional Components

The bituminous composition may also, optionally, contain otheringredients such as may be required for the end-use envisaged. Thusfillers may be included, for example talc, calcium carbonate and carbonblack. Other components that may be incorporated include resins, oils,stabilisers or flame retardants. The content of such fillers and/orother components may be in the range of from 0 to as much as 40% wt(based on the total bituminous composition). Of course, if advantageous,other polymer modifiers may also be included in the bituminouscomposition of the invention.

The useful low temperature and high temperature properties of thepolymer-bitumen blends of the present invention coupled with theimproved ageing resistance enables such blends to be of significantbenefit in uses where the blends are exposed to external weatherconditions, such as use in roofing applications, for example as acomponent of roofing felt. The usefully low high-temperature viscositynot just means that the polymer-bitumen blends can be more easilyprocessed but also means that they enable a greater amount of filler tobe incorporated before the maximum allowable processing viscosity isachieved, and thus leads to a cheaper product in those applicationswhere fillers are commonly used.

Combining the Components

The components of the compositions of the present invention can becombined in way known to those of ordinary skill in the art of preparingbituminous compositions to be useful. For example, the bitumen, additiveand elastomer can be combined sequentially. In an alternative embodimentof the present invention, the elastomer and additive can first beadmixed, and then the combination of elastomer and additive can then beadmixed with the bitumen. In a preferred embodiment, the additive can beadded to the elastomer during elastomer production.

EXAMPLES

The following examples are provided to illustrate the present invention.The examples are not intended to limit the scope of the presentinvention and they should not be so interpreted. Amounts are in weightparts or weight percentages unless otherwise indicated.

Bituminous Compositions

Master batches with 12% wt KRATON® D-1184 (a commercial SBS grade,having an apparent radial MW of 420,000 g/mol, a diblock MW of 120,000g/mol a PSC of 30% wt and a vinyl content of 8% wt) in two types ofcommercially available bitumen, i.e. B 45/60, and B 160/210, are madewith a SILVERSON® L4R high shear mixer. The bitumen is heated to 160° C.and subsequently the polymer is added. Upon blending, the temperatureincreases to 180° C., which is caused by the energy input from themixer. Blending at this temperature is continued until a homogeneousblend is obtained which is monitored by fluorescence microscopy.

With these master batches, bituminous compositions are prepared usingthe other ingredients under low shear stirring at a temperature of 180°C.

Test Methods

A standard evaluation on the blends without filler, i.e. thedetermination of softening point, viscosity, DIN flow resistance andcold bend, is carried out.

The penetration at 50° C. of each composition in this study is alsodetermined. The load applied on the surface of a composition during apenetration measurement calculation is as follows:

-   -   the cone tip diameter of the needle used is 0.15 mm (as reported        in the calibration report and defined in ASTM D5-94);    -   the surface of the needle (0.25×n×d²) is 0.0177 mm2;    -   the total load applied during the measurement, i.e. the weight        (50 g) and bar, amounts 100 g.        Therefore, the actual load is: 100/0.0177=5650 g/mm2=56500 kPa.

The indentation and resilience is determined as follows: if the surfaceof an average shoe size is 210 cm2 (30×7 cm) and the weight of anaverage person is 80 kg, the load which is exerted on the roof(80/210=0.394 kg/cm2) is 38 kPa.

The experiments are carried out on the compositions in penetration cups.On the surface of the composition a round flat metal cylinder is placedwith a diameter of 1.3 cm. In this study the indentation tests arecarried out by applying two different loads, i.e. 0.5 kg and 1 kg. Theactual loads exerted upon the compositions are therefore: 38 kPa and 76kPa.

Creep tests are done for each composition at 50° C. applying variousloads. The creep test is performed with a Haake RT20 Rotoviscometerusing a parallel plate configuration. The diameter of the upper plate is8 mm, while the distance between the plates is 1 mm. The initialthickness of the samples used is 1.5 mm. Before the start of themeasurement the samples are trimmed. The creep tests are carried outapplying a constant load of 40 kPa, 20 kPa, 10 kPa or 5 kPa. Thecompliance J (1/Pa) as a function of time is been determined for eachcomposition.

Experiments 1-5

IRGANOX MD-1024 is used in this study to investigate its effect on thepenetration of typical roofing composition based on standard D-1184 SBSand 30% wt filler.

Results

The results of the penetration tests at 50° C. are given in the Table.The penetration values of the reference composition without theadditives present is given for comparison reasons. Furthermore, thetypical performance properties of a composition with bitumen B45/60 arealso given for comparison reasons. TABLE Experiment No. A 1 2 3 BMD-1024, % wt nil 0.1 0.3 0.5 nil Bitumen (B160/210 B160/ B160/ B160/B160/ B45/60 or B45/60) 210 210 210 210 Pen at 50° C., dmm 94 99 82 6766 Indent 50° C., 36 32 12 9 38 kPa, dmm Indent 50° C., 69 60 26 16 76kPa, dmm R&B, ° C. 124 125 123 122 134 Visco, 180° C., Pa · s 20 s−1 5.24.9 5.9 6.6 8.1 100 s⁻¹ 3.7 3.9 4.6 5.6 8.5 Cold bend, ° C. pass −35 −35−40 −40 −5 Flow, ° C. pass 95 95 95 95 110

CONCLUSION

The presence of MD-1024 significantly affects the penetration of thecomposition at 50° C. It is also demonstrated that the quantity of theadditive influences the level of penetration.

It is demonstrated that with 0.5% wt MD-1024 present in a compositionwith the softer B160/210 bitumen a similar penetration value at 50° C.is obtained in comparison with that found for a composition with theharder B45/60 bitumen, while significantly better overall performanceproperties are found for the composition with the softer bitumen.

The penetration at 50° C. was reduced significantly, which suggests thatthe level of indentation should be improved as well.

The results of the indentation and resilience of the compositions withD-1184 in B160/210 bitumen, filler and additive applying an excessiveload of 76 kPa are reported in FIG. 1. The results for the referencecomposition, i.e. without additive present are also given.

A major improvement of the level of indentation has been establishedwith the presence of the additive, without affecting the resilience. Ineach case a total recovery within 120 seconds has been observed.

With the creep test the resistance to deformation has been determined at40 kPa at a temperature of 50° C. The results for each composition(B160/210) as reported in Table 1 are given in FIG. 2. With the presenceof the additives the resistance to deformation was improvedsignificantly.

If 0.3% wt or even more pronounced 0.5% wt MD-1024 is incorporated in atypical roofing composition the walk-on-ability, i.e. penetration,indentation and resilience and resistance to deformation, can beimproved substantially.

1. A bituminous composition comprising a bituminous component (A), atleast one elastomer component (B) selected from the group consisting ofpolydienes, copolymers of dienes with a monovinylaromatic hydrocarbon,polyacrylates, polysulfides, polysilicones and polyesteramides havingelastomeric behavior, and an additive (C), wherein the additive is acompound having the general formula:Ar—R—Ar  (I) wherein each “Ar” independently is a benzene ring or fusedaromatic ring system of 6 to 20 carbon atoms, substituted by at leastone hydroxyl group, and “R” is represented by the formula:—R¹C(═O)X—R²XC(═O)R¹—  (V) wherein each “R¹” is a C1-4 hydrocarbonylenegroup, “R²” is a C1-10 hydrocarbonylene group, and “X” is a nitrogenatom; and “n” is an integer having a value from 1 to 4, said elastomercomponent (B) being present in an amount in the range of from about 2 toabout 20% wt and said additive (C) being present in an amount in therange of from about 0.01 to about 5 weight percent, based on the totalbituminous composition.
 2. The bituminous composition of claim 1 whereinthe elastomer component is a block copolymer of a conjugated diene and amonovinylaromatic hydrocarbon.
 3. The bituminous composition of claim 1,wherein the bituminous component is naturally occurring bitumen orderived from a mineral oil.
 4. The bituminous composition of claim 3,wherein the bituminous component has a penetration in the range of fromabout 50 to about 250 dmm at 25° C.
 5. The bituminous composition ofclaim 2, wherein the block copolymer used as elastomer component (B)comprises at least two terminal blocks of a poly(monovinylaromatichydrocarbon) and at least one block of one or more conjugated dienes ora partially hydrogenated version thereof.
 6. The bituminous compositionof claim 5, wherein the conjugated diene is selected from the groupconsisting of butadiene, 2-methyl-1,3-butadiene (isoprene),2,3-dimethyl-1,3-butadiene, 1,3-pentadiene and 1,2-hexadiene, andmixtures thereof.
 7. The bituminous composition of claim 6, wherein themonovinylaromatic hydrocarbon is selected from the group consisting ofo-methyl styrene, p-methyl styrene, p-tert-butylstyrene,2,4-dimethylstyrene, α-methylstyrene, vinyl naphthalene, vinyl toluene,vinyl xylene, and mixtures thereof.
 8. The bituminous composition ofclaim 7, wherein the monovinylaromatic hydrocarbon is styrene.
 9. Thebituminous composition of claim 7, wherein the content ofmonovinylaromatic hydrocarbons of the block copolymer ranges from about10 to about 70 weight percent based on the total block copolymer. 10.The bituminous composition of claim 14, wherein the polymer blocks ofmonovinylaromatic hydrocarbons have an apparent molecular weight in therange from about 2,000 to about 100,000 and the polymer blocks ofconjugated dienes have an apparent molecular weight in the range of formabout 25,000 to about 1,000,000.
 11. The bituminous composition of claim14, wherein the total vinyl content of the block copolymer is at least 6weight percent based on the blocks of poly(conjugated diene).
 12. Thebituminous composition of claim 1 wherein the elastomer component (B)comprises at least two terminal blocks of a poly(monovinylaromatichydrocarbon) and at least one block of one or more conjugated dienes ora partially hydrogenated version thereof, “R¹” is C2 hydrocarbonyleneand “R²” is C6 hydrocarbonylene.
 13. A roofing felt comprising (i) abituminous composition comprising a bituminous component (A), at leastone elastomer component (B) selected from the group consisting ofpolydienes, copolymers of dienes with a monovinylaromatic hydrocarbon,polyacrylates, polysulfides, polysilicones and polyesteramides havingelastomeric behavior, and an additive (C), wherein the additive is acompound having the general formula:AR—R—Ar  (I) wherein each “Ar” independently is a benzene ring or fusedaromatic ring system of 6 to 20 carbon atoms, substituted by at leastone hydroxyl group, and “R” is—R¹C(═O)X—R²XC(═O)R¹—  (V) wherein “R¹” is a C1-4 hydrocarbonylenegroup, each “R²” is a C1-10 hydrocarbonylene group, “X” is a nitrogenatom; and “n” is an integer having a value from 1 to 4, said elastomerbeing present in an amount in the range of from about 2 to about 20% wtand said additive (C) being present in an amount in the range of fromabout 0.01 to about 5 weight percent, based on the total bituminouscomposition; and (i) a filler selected from the group consisting oftalc, calcium carbonate and carbon black.
 14. The roofing felt of claim13 wherein the elastomer component (B) comprises at least two terminalblocks of a poly(monovinylaromatic hydrocarbon) and at least one blockof one or more conjugated idenes or a partially hydrogenated versionthereof, “R¹” is C2 hydrocarbonylene and “R²” is C6 hydrocarbonylene.15. A process for preparing a bituminous composition comprising admixinga bituminous component (A), at least one elastomer component (B)selected from the group consisting of polydienes, copolymers of dieneswith a monovinylaromatic hydrocarbon, polyacrylates, polysulfides,polysilicones and polyesteramides having elastomeric behavior, and anadditive (C), wherein the additive is a compound of the general formula:Ar—R—Ar  (I) wherein each “Ar” independently is a benzene ring or fusedaromatic ring system of 6 to 20 carbon atoms, substituted by at leastone hydroxyl group, and “R” is represented by the general formula:—R¹C(═O)X—R²XC(═O)R¹—  (V) wherein each “R¹” is a C1-4 hydrocarbonylenegroup, “R²” is a C1-10 hydrocarbonylene group, and “X” is a nitrogenatom; and “n” is an integer having a value from 1 to 4, said elastomerbeing present in an amount in the range of from about 2 to about 20% wtand said additive (C) being present in an amount in the range of fromabout 0.01 to about 5 weight percent, based on the total bituminouscomposition.
 16. The process of claim 15 wherein the elastomer componentand the additive are admixed with each other prior to being admixed withthe bituminous component and wherein the elastomer component (B)comprises at least two terminal blocks of a poly(monovinylaromatichydrocarbon) and at least one block of one or more conjugated idenes ora partially hydrogenated version thereof, “R¹” is C2 hydrocarbonyleneand “R²” is C6 hydrocarbonylene.
 17. A composition useful for preparingor repairing roofs, said composition comprising (i) a bituminouscomposition prepared by admixing a bituminous component (A), at leastone elastomer component (B) selected from the group consisting ofpolydienes, copolymers of dienes with a monovinylaromatic hydrocarbon,polyacrylates, polysulfides, polysilicones and polyesteramides havingelastomeric behavior, and an additive (C), wherein the additive is acompound of the general formula:Ar—R—Ar  (I) wherein each “Ar” independently is a benzene ring or fusedaromatic ring system of 6 to 20 carbon atoms, substituted by at leastone hydroxyl group, and “R” is represented by the general formula:—R¹C(═O)X—R²XC(═O)R¹—  (V) wherein each “R¹” is a C1-4 hydrocarbonylenegroup, “R²” is a C1-10 hydrocarbonylene group, and “X” is a nitrogenatom; and “n” is an integer having a value from 1 to 4, wherein theelastomer component and the additive are admixed with each other priorto being admixed with the bituminous component for preparing orrepairing roofs, said elastomer component being present in an amount inthe range of from about 2 to about 20% wt and said additive (C) beingpresent in an amount in the range of from about 0.01 to about 5 weightpercent, based on the total bituminous composition; and (ii) a filler.18. The composition of claim 17 wherein the elastomer component (B)comprises at least two terminal blocks of a poly(monovinylaromatichydrocarbon) and at least one block of one or more conjugated idenes ora partially hydrogenated version thereof, “R¹” is C2 hydrocarbonyleneand “R²” is C6 hydrocarbonylene.